Carburetor



, 1929. w, E. s. STRONG GARBURETOR April 30 Filed March -5, 1922 INVENTOR ,.lllllllllllllullliwx Patented Apr. 3o, v1929.

lJNlTED STATES girri'riz'ivr oFFicE.

WILLIAM. n. s. s'rRoNe, or NEW YORK, N f Y., AssieNon To WILLIAM 1. DEPP, or

NEW YORK, N. Y.`

CARBURETOB'.

Application filed March 3,

My improvement relates more particularly 2 to a carburetor provided With primary and secondary air conduits, and fuel nozzles, the mixture formed therein united in a common mixing chamber Which is provided With a centrally opening throttle valve. A. carbu'- retor of this type is shown and described in a patent to "William P. Deppe, No. 1,163,228 of December 7, 1915, and my invention relates to improvements, not only in the centrally opening throttle valve, but in other featuresv of theucarburetor. Y One object of my improvement is to provide a cent-rally opening throttle valve, in which the valve members are balanced and this is accomplished by making the valve members cylindrical and providing each member With a cylindricalnotch or recess, extending transversely of the respective cylinders and approximately to the axes thereof. The cylindrical members are provided With axial spindles and are mounted in parallel relation, so that adjacent surfaces are in contact, the valve being closed When the recesses are out of register. Y

The tWo cylindrical members of the valve are geared together to rotate in unison in opposite directions and the valve may be opened `or closed by attaching the usual cranl; lever to thespindle of one of the cylindrical members. y

Another object of my improvement is to form the cylindrical valve members and the Vtrunnions thereof hollow or tubular, preferably made up of two similar sheet metal stampings, brazed or Welded together to form a single unit. It is frequently desirable in utilizing low grade fuels in carburetors, to provide for heating the mixture at certain stages after it passes through the mixingvchamber and in order that this may be satisfactorily accomplished, as the mixture leaves the carburetor, the hollow cylindrical valve members of my centrally opening throttle valve may preferably be supplied With exhaust ygases from the engine, Which, passing therethrough, Will heat the valve members and particularly the surfaces exposed to the mixture passing therethrough 1922.A Serial No. 540,689.

When the valve is partially open. Obviously, the amount and method of circulating the exhaust gases through the valve members may be varied according to the requirements ofl any particular lay-out or engine.

Itis frequently desirable, particularly in carburetors for trucks to provide a second throttle valve, to be controlled automatically by a governor to thereby automatically limit the speed of the engine and, therefore, another object of my improvement is to show how two centrally opening throttle valves may be employed for this purpose. When two such throttle valves are employed, OHG 0if 'them will be connected for manual operation lcylindrical, throttle members, when such heated valves are desired or required in the operation, of theengine.

In carburetorsof this type, and particularly When used With low grade gasoline orl fuel oils, it is desirable that all the air passed through the carburetor should be preheated, preferably from stoves or' heaters surrounding the exhaust pipe. In this conneetion'anotherA object of my improvement is toprovide for a single air inlet pipe for supplying heated air for both the primary and secondaryair conduits. With this improved construction, uniformity in temperature of the. airl supplied to and passed through the respective conduits of the carburetor Will be assured and the choke valve in the single air inlet pipe Will be adapted to control the opening of the auxiliary valve by equalizing the vacuum pressure in the carburetor. In this manner I am enabled to simplify the mechanism by eliminating the usual connection between the choke valve and the auxiliary valve.

Further it will be noted that in this manner oi heating the throttle valve, the use of hollow cylindrical members, permits the largest possible area of metal exposed both to the heating` Huid and to the fluids to be heated in a given space.

lt permits the sections to be remote enough from the carbureting devices so as not to unduly heat the metals associated therewith, and cause boiling of the l'uels in the supply bowl or the nozzles, which will result in irregular ilow of the fuels, which irregularity will vary with the change of temperatures, throttle opening and engine speeds.

Furthermore, this improved construction of the throttle valve avoids sticking or parts such as would prevent proper operation, makes for light weight and low cost construction, and provides a regulated heat control oi the throttle valve which cannot be obtained by electrical means.

ln View oi the fact that in actual operating conditions, a careful check up indicates th at the throttle is wide open less lthan 10% ol the total operating time, this construction ot the throttle produces a sheeting etllect on the stream oit the mixture, with heat applied on both sides thereof, for 'the greater portion oi the operating time, the sheeting and heating effect being greatest when most needed, that is, with smaller opening oi' the throttle, thus facilitating rapid vaporization and eilicient operation.

Where the duplex throttle valves are used, one tor the usual manual control operation and one to act as a governor valve, this construction aliords two successive stages of heat application, with an intervening chamber permitting expansion and agitation of the mixture, thus eii'ecting vaporization under equilibrium conditions instead of by fractional distillation.

It will be obvious that my improved carburetor may be provided not only with two centrally opening throttle valves -lor use on trucks but with a single centrally opening tl'irottle valve when used on pleasure cars and the like, and both forms are represented in the accompanying drawings, in which vFig. 1 is vertical section through the middle of the carburetor, transversely of the centrally opening` throttle valves; Fig. 2 is a horizontal section on the line QMQ of Fig. l, indicating the construction and arrangen'ient oi trie throttle valve members; Fig. 3 is a liront elevation ot the throttle valve portion of the carburetor, when provided with a single 'throttle valve.

Referring to the drawings, l is the 4float tank ci carburetor, which is connected through the tubular channel 2 with a vertically ente-ruling channel 3, the upper end of which is provided with the primary nozzle 4i, as more particularly shown in Fig. l or the drawings. :from the channel 3 into af vertical bore or channel 6, in which is loca-ted the secondarynozzle 7.

rilhe primary nozzle 4l opens or projects into the lower end of the Venturi tube 8, which is preferably removably inserted and held in place by a suitable screw 9, thereby providing for a change in the size or diameter oiI the Venturi tube, according to the conditions or requirements or" the engine. The upper end et the Venturi tube 8 extends into a cylindrical mixing chamber l0, in which the throttle valve is mounted.

ln my improved carbiiiretor, as will be seen in Figs. l and 3 the throttle valve is oi? the type known as centrally opening, in that the opening between the valve members takes place central or axially of the mixing chamber lll and thus completely eliminates any possibility of detlecting the mixture to 'the walls of the passage, (as is done by the common butterfly valve), the mixture being always retained centrally thereof. in my improved centrally opening throttle valve two cooperating members are used, cach member pre rer-ably cou'iprising a cylindrical portion il provided with trunnions l2, the two cylindrical members being mounted in bored-out cavities in the head 13. A. plate lll is provided igor closing the bore opening on the side oi' the head 13, the plate being secured thereto by screws i5, so that it may be removed for the insertion or removal oi the valve members ll. rlhe valve members ll.-l2 are preferably provided with semicylindrical. recesses 1G, in the periphery of the eylirulrical portions ll and extending substantially to the axes oit the respective cylinders. rihcse recesses are adapted to register when mounted in the casing or head i3, to torni the valve opening when the cylindrical valve members are ro y.rted out -ol' the closed position shown by the upper valve oit Fig. l, and toward the position shown the fr valve in Fig. l, where the valve niemc. a shown with the valve fully open.

rEhe two cylindrical valve members li with 'their trunnions l2 are preferably tfrnied hollow by being wiped oit sheet metal in two halves which secured together by blazing or weldi as indicated by diametral lines in F l.. llt will be seen that, from 'this construction the two halves oi' the cylindrical inemb may be stamped or d rawn of sheet metal. in the same die, the two halves being substantially as infin-ated by the two halves shown in section vin Fig. 2. ll be seen that it one ot the h alt 'ions in 2 were turned over onto the other, they would 'form the complete cy lindri zal me riber with the semi-cylindrical recess and this illustrates substantially the way the members are made.

it branch channel 5 leads lt willbe seen that the hollow cylindrical const-ructionof the valve members not only represents a saving of metal and a lightening et the valve members, but enables me to heat the respective valve members by pass- -ing` hot' exhaust gases therethrough as moreA lully described hereinaiter. The cylindri-` cal members ll of the valve are' mounted se that the cylindrical surfaces will be substantially in contact, as shown by the upper valve in Fig. l of the drawings, therebycutting ofi the passage therebetween of any mixture. lt will be seen, however, that `by rot-ating the valve members in opposite directions, the cylindrical recesses 16 will come into register, first with a. narrow opening, which will increase in size as the cylindrical members areV rotated untilv they Vhave been rotated a quarter turn each, lin which position the valve will be fully open as indicated by the lower valve in Fig. l of the drawings. lt will be seen that, at all times, the valve opening will be V'centralV or axial of the mixing chamber. ln order that the'two valve f members may be rotated simultaneously in opposite directions, they are preferably geared together, by suitable gears i7, which interinesh as indicated in Fig. 201Y the drawings. One of the trunnions 12 ol' each pair ot valve members is provided with a cranlr arm .i8 secured thc-reto by clamping the split end ot the arm by means oi'f a suitable screw 19. l'lihe crank arm 18, adjacent the trunnion l2 is provided with laterally extending arms or lugs-20, eachy provided with a screw 21 adapted to cooperate with a' vertical ribk 22 projecting from the plate ll or from the wall ot the valve head 13, as indicated in Fig. 3, for limiting the rotative movement oi the arins 18 to one quarter ot a turn and for adjusting the point of closingV of the valve, so that when desired, a small crack or opening` may beleit for idling the engine.

in the two throttle valve carburetor, as shown in Fig; l 'of the drawings, it will be obvious that either the Yupper or lower throttle maybe connected with the usual manual control and the other throttle connected with a governor; The throttle connected with the governor will be proper tionately closed according to the speed oi' the engine. rlhis particular type of carbu'- retor is therefore, adapted for use in connection with trucks where it is desired to limit the speed. Nhen the engine is at rest, or idling, the governorl throttle may beso adjusted as to be wideopen, as indicated by the position of the lower throttle in Fig. 'l oit the drawings, and adaptedto be rotated toward the closed position as the speed of the engine increases. The upper throttle in this view is shown completely closed, but as previously stated, i' desired, the position of the crank arm lS'may be varied, so that it will be impossible to completely'close the .the same reference characters.

' A further improvement of my. carburetor relates to the admission oi. heated air tothe carburetor. In caiburetors et this form, provided with primary and secondary nozzles, it is usual to have separate inlet openings for .each nozzle, the inlet opening for `the auxiliary air being controlled by a valve under spring tension, so adjusted as to open when the vacuum pressure within the `carburetor reaches a predetermined point. In my improved carbureton: the primary air passes through the conduit 23 and up past the primary nozzle et and through the venturi to the mixing vchamber l0. The sec- Aond'aryair passes over the secondary nozzle 7 in the secondary air conduit 24E, which,

will be seen from Fig. l of the drawings, ent-ers the mixing chamber 10 whereV both primary and secondary mixtures are united, andthe flow thereof controlled by the centrally opening throttle valve. VThe secondary air conduit 24 -isfpreierably formed or connected 'as a branch of the primary air conduit through an opening 25, which is provided with a valve 26, adapted tov be seated thereon, under tension ot a suitable spring 27. Thev auxiliary air vchamber. 24,

vided with an'opening or hand hole 28 for access to the inner wall of the conduit when forming the valveseat and for yproperly insertinggthe -valve in place. The opening 28 is closed by a cap 29, in which an adjusting nut 30 is screw threaded, a loclr nut 3l being provided for holding the nutl() in any adjusted .-position.'` The valve 26 is provided with valve rod or stem 32, extending upwardv through a hole in the adjustable cap screw 30, the adjustable screw 30 being thereby adapted for adjusting` the tension `above the valve 26, may preferably be4 proon the spring 27. In this manner, it will be seen rvthat the vacuum pressure at which the valve 26V will open can be varied as required.

Thevalve rod 32--is reduced in size at 33, where the valve is attached thereto by crimping or spinning the metal into the groove thus formed. The lower end 3d olf the rod extends below the valve and through a bushing 85 screwed into the lower wall ot the primary air conduit, sulistantially4 as indicatedin Fig. l ot the drawings. A lock nut 36 may be. provided forv holding lthe bushing nut 35' in proper place. The lower end of the rod 34 is threaded at 37 and provided with a nut 38 and lock nut 39 cooperating with a secondary spring 4() seated between the nut 38 and the lower turned down end of the bushing nut 35. The spring 40 is adapted to be brought into operation only after the valve has been lifted a predetermined amount, to thereby increase the resistance to lifting and control the auxiliary air passing through the valve. A cap 41 is screwed on to the lower end of the bushing screw 35 for protecting the spring 40 and associated parts. In order that the valve 26 may be more sensitive and operate substantially independent of gravity, it is preferable to provide a spring 42, surrounding the lower valve stem 34 for counter-balancing the weight of the valve. By this construction, it will be seen that the opening of the valve 26 to admit auxiliary air to the secondary nozzle may be controlled by the tension on the spring 27 and the tension on the spring 27 may be varied by adjusting the cap nut 30, as previously indicated. The point at which the secondary spring 4() comes into action may be varied by adusting the nuts 38 and 39, as will be readily understood from an inspection of the drawings.

The primary and secondary or auxiliary air is adapted to be drawn through a single tubular conduit 43, which is preferably provided with the usual choke valve 44, which may be brought into operation when start* ing the motor in the usual manner. In my improved construction, however, it will be seen that the choke valve automatically controls the auxiliary valve 26 and the latter is prevented from opening when starting the engine because the vacuum pressure is the same on both sides of the valve 2G'and there will be no tendency for the valve to open. The pipe 43 forming the single conduit opening for supplying both primary and auxiliary air to the carburetor may be con nected in the usual manner by means of flexible metal tubing (not shown) with a suitable supply of highly heated air. This construction has the advantageof providing heated air of the same temperature for both the primary and auxiliary conduits through the carburetor.

ln carrying out my improvement for heating` the throttle valve members, it will readily be understood that a flexible metal pipe or other suitable means may be connected with the exhaust pipe or manifold of the engine and arranged to conduct exhaust gases through a T-shaped tubular bracket 47 secured to the rear face of the carburetor valve head 13 by suitable screws 48, as indicated in Fig. 2. The exhaust gases will enter the branching tube through the opening 49, and dividing will pass, as indicated by the arrows in Fig. 2, through the trunnions 12 of the respective cylindrical valve members 11, and out through the opposite trunhions 12. The bracket 47 is provided with two holes adapted to surround the respective trunnions 12 and counterbores are provided at 50, for engaging the bearing bosses '51,in which the trunpions 12 rotate. By this construction, it will be seen that a tight joint will be formed between the casing 13 and the T-shaped tubular member 47, through which the exhaust gases are adapted to pass and yet the valve members 11 will be free to rotate on their trunnions 12. The hot exhaust gases passing through the tubular valve members 11 will strike the inner walls of the semi-cylindrical valve opening surfaces 16 and heat the latter. When the valve members aie in partially open position, it will be seen that a larger proportion of the heated valve area will be exposed to the impact of the mixture than when the valve is fully opened. This is desirable in that at full opening, the amount of heat required under certain conditions may not be s great as when the valve is partially open.

lt will be understood that while I have shown the preferred formrof my improved carburetor, and the centrally opening heated throttle valves, l do not wish to be limited to the specific construction shown and described, for various modifications in the adaptation of the valves and the heating thereof, as well as in the construction of the auxiliary air valve, may be made without departing from the spirit and scope of the invention.

l claim 1. ln a Acarburetor wherein the fuel and air are mixed in a mixing chamber located above the nozzle, a centrally opening throttle valve at the outlet of the mixing` chamber, comprising a pair of valve members formed as hollow cylinders with hollowtrunnions and mounted in parallel relation so that adjacent faces of the cylinders contact, said cylinders being indented transversely. of their axes with semi-cylindrical recesses adapted to form the throttle valve opening, and means cooperating with said hollow trunnions for passing hot exhaust gases through both valve members, the arrangement being such that at partially open throttle the mixture passing therethrough is shceted and heated on both sides.

2. In a carburetor, wherein the fuel and air are mixed in two successive mixing chambers located above the nozzle, centrally opening throttle valves at the outlets of the successive mixing chambers, through which the mixture is adapted to pass in succession, each throttle valve comprising a pair of valve members formed of hollow cylinders with hollow trunnions, said cylinders being indented transversely of their axes with recesses adapted to cooperate and form the valve opening, and means associated With the respective trunnions for passing hot exhaust gases through the valve members of both valves for heating the same, the mixing chamber between said throttle valves being adapted to provide an expansion chamber for agitating the mixture after being heated by passing the first valve, the arrangement being such that the tWo valves under normal 10 operation are adapted to successively sheet and heat the mixture in stages.

WILLIAM E. S. STRONG. 

